Tissues and Supporting Systems - SS1 Biology Past Questions and Answers - page 2

Vascular tissue

Endoskeletons and exoskeletons are two distinct types of skeletal systems found in different organisms. An endoskeleton is an internal skeletal framework present within the body of an organism. It provides structural support, protects vital organs, and serves as an attachment point for muscles. Endoskeletons are commonly found in vertebrates, including humans, and are composed of bones or cartilage. The flexibility and adaptability of endoskeletons allow for efficient movement and growth.

On the other hand, an exoskeleton is an external skeletal structure that surrounds the body of an organism. It functions as a protective shield against predators, physical damage, and desiccation. Exoskeletons are typically composed of a tough and rigid material such as chitin, which provides strength and stability. Organisms with exoskeletons, such as insects, crustaceans, and some mollusks, undergo molting or shedding of their exoskeletons to accommodate growth.

The human skeleton can be divided into two main parts: the axial skeleton and the appendicular skeleton. The axial skeleton consists of the central axis of the body, including the skull, vertebral column, and rib cage. It provides support and protection to vital organs, such as the brain, spinal cord, and heart. The appendicular skeleton, on the other hand, includes the bones of the limbs, including the arms, legs, shoulder girdle, and pelvic girdle. It is responsible for facilitating movement, locomotion, and manipulation of objects. In summary, the axial skeleton focuses on protecting and supporting vital organs, while the appendicular skeleton is involved in movement and locomotion.